<div id="left_content">
    <table class="table" cellpadding="0" cellspacing="0">
                        <thead>
                            <tr class="lecture">
                                <th>Cấu trúc chuyên mục</th>
                            </tr>

                        </thead>

                        <tbody>

                            <?= $tree_menu?>

                        </tbody>
    </table>
</div>